This invention relates to a gripper system, and more particularly, relates to a gripper system for moving drilling rigs supported on flanged skid bases of an offshore drilling platform.
Offshore drilling platforms are used to drill a number of holes. That is, a single platform may be used to drill or sink numerous wells, sometimes as many as twenty or more from the same platform. Thus, each time a well is sunk, the drilling rig must be repositioned for drilling in a different area or at a different angle. The drilling rig is mounted on flanged skid bases to permit sliding the rig from position to position for drilling successive wells. Previously, a cumbersome and time-consuming mechanical block-and-tackle jacking system was used to move the drilling rig, or slots were cut in the skid beams for use with slide frogs to move the drilling rig. It would be preferable if such movement of the drilling rig could be automated to considerably reduce the time and efficiency for moving the drilling rig from one position to another on the drilling platform. Further, cutting slots in skid base is a costly and time consuming fabrication process.